This invention relates to storage racks and, more particularly, to improved versions of storage rack assemblies designed for high density storage of goods delivered by power driven lift equipment such as fork trucks.
Since warehouse space for storage of goods is expensive, there are many advantages to an efficient and well organized vertical storage rack system which will allow the storage of goods in an orderly fashion. Since the products are stacked vertically, optimum use of the floor space may be achieved. The disadvantage is that the goods to be stored must now be raised to the height of the rack where they are to be stored. The moving and especially the raising of the goods is most efficiently accomplished via fork trucks.
In as much as fork trucks require aisles to travel to the desired location to either store or retrieve goods from a particular rack, this aisle space is not available for storage. To maximize the storage area given a limited number of square feet in a building or warehouse, one must minimize the area reserved for aisle space for the fork trucks.
Unfortunately, as one reduces the size of these aisles, the room to maneuver for the fork trucks is also reduced, and the end result is that the fork trucks sometimes hit the storage racks, damaging the fork trucks as well as the storage racks.
Prior art (Konstant U.S. Pat. No. 3,785,502; Klein U.S. Pat. No. 4,117,938) has taught the use of recessed legs towards the bottom of the rack in order to give more room to maneuver to the fork trucks at the ground level. This has typically been accomplished by angling back the front legs (the legs closest to the aisles), which puts these legs out of harm""s way. However, the weight of the storage rack and of the goods stacked thereupon is then concentrated on this angled leg, and substantial use of struts and reinforcing members is required. This makes it very difficult, if not impossible, to retrofit existing storage racks in the field. The retrofit, if possible, is difficult, expensive, and time consuming, and requires specialized skills, such as a good welder to complete the task. Furthermore, while the bottom of the angled legs is far removed from the aisles, the closer one gets to the top portion of the angled legs, the closer one is to the aisle and to the distinct possibility of having a fork truck run into the angled leg. Also, since the prior art designs use the same upright members for the entire storage rack, the only way to beef up one portion of the upright is to beef up the entire height of the rack.
The present invention provides an offset frame, which may be field-installed by bolting onto a storage rack. This design provides the following distinct advantages over the prior art:
The base is designed and manufactured as a completely separate piece from the storage rack itself. Thus, an existing storage rack may be raised (or cut off) and placed on top of the base without any additional bracing, struts, or reinforcing members being required of the existing structure. Furthermore, for completely new installations, manufacturing the top and bottom sections separately makes both of them easier to manufacture and install.
The base is designed with the front legs (closest to the aisles) offset back from the aisle. These front legs are substantially vertical, such that the entire leg is set back and away from where the fork trucks travel.
Since the base is a completely separate member, it may be made of heavier members than the rest of the rack in order to support the cantilevered storage rack load without increasing the cost of the rest of the rack. Indeed, all the base members may be made from heavy structural members that enhance the frame""s strength and abuse resistance, while the storage rack itself may be manufactured of lighter gauge materials to save on manufacturing costs and to reduce the weight of the structure.
The present invention simply bolts a cantilevered base onto the bottom of a storage rack, which readily permits modification of existing frames in the field to turn an ordinary rack into an offset rack. Using separate base and top members, using heavier structural members for the base than for the top, and the all-bolted capability contribute to this ease of retrofitting an existing storage rack.